Extensible tool for handling energized electric equipment

Abstract

The tool comprises a plurality of tubular telescoping sections of insulating material arranged in a series. Each of the sections, except a most rearward end section, has a forwardly facing annular exterior shoulder at its rearward end and each of the sections, except a most forward end section, has a rearwardly facing annular interior shoulder at its forward end. When the tool is fully extended for use, each rearwardly facing shoulder engages a forwardly facing shoulder and radial apertures in the sections are in alignment. A pin support located within the rearward end of each section except the most rearward section contains a pin which is biased outwardly by a compression spring through the aligned apertures thus locking the sections in their extended positions with respect to each other. The pins, aligned openings, and shoulders are relatively positioned so that pulling forces are opposed by the shoulders and not the pins.

I claim: 
     
       1. An extensible tool for handling energized electrical equipment comprising: a. a plurality of telescoping cylindrical tubular sections of insulating material each having a longitudinal passage and arranged in series so that the tool when extended is of reduced transverse cross section progressively from a rear to a forward end, each of the sections except a most rearward section having an outer diameter of such size that it slidably fits in the next rearwardly adjacent larger section;   b. a rearwardly facing annular interior shoulder positioned near the forward end of each of the sections except a most forward section;   c. a forwardly facing annular exterior shoulder positioned near the rearward end of each of the sections except the most rearward section and defined by an edge face of a ring surrounding its associated section and bonded to the exterior surface of the section;   d. a first radial aperture in each section except the most forward section positioned forwardly of and adjacent to the rearwardly facing shoulder of its section;   e. a second radial aperture in each section except the most rearward section positioned forwardly of and adjacent to the forwardly facing shoulder of its section;   f. each forwardly facing shoulder, when the tool is fully extended, being in engagement with the rearward facing shoulder of the next adjacent larger section and the first apertures being in substantial alignment respectively with the second apertures;   g. a pin support disposed within each section except the most rearward section and having a cavity coaxial with the second aperture of its section; and   h. a pin and a spring disposed within each cavity, each spring biasing its associated pin radially outwardly for causing an end portion of its associated pin to extend into the second aperture of its section, and, when the tool is fully extended, for causing the end portion of its associated pin to extend into the first aperture of the next larger section, thereby to lock the sections in their extended positions with respect to each other.   
     
     
       2. An extensible tool as claimed in claim 1 wherein each section is formed by a molding process and the annular exterior shoulder thereon is formed during the molding process. 
     
     
       3. An extensible tool as claimed in claim 1 wherein each pin support only partially blocks the passage through its associated section and has opposed curved end portions fitted snugly against the interior of the passage. 
     
     
       4. An extensible tool as claimed in claim 1 wherein each first aperture is larger than its associated second aperture, each associated first and second aperture are positioned relative of each other when the shoulders of their respective sections abut so that a gap exists between the forward side of the pin and the forward edge of the first aperture end whereby longitudinal pulling forces on the tool are borne only by the shoulders. 
     
     
       5. An extensible tool as claimed in claim 1 wherein each pin support has a rearward end face generally coplanar with the rearward end face of its associated section. 
     
     
       6. An extensible tool as claimed in claim 1 wherein each support has a diameter less than any portion of the rearward end of its associated section. 
     
     
       7. An extensible tool as claimed in claim 1 wherein the shoulders are radially disposed with respect to the longitudinal axes of their associated sections. 
     
     
       8. An extensible tool as claimed in claim 1 wherein the most rearward section has a rear radial aperture near its rearward end and a cap is positioned in the rearward end of the passage of the section, the cap has an apertured flange portion blocking entry to its passage, a shank portion provided with curved portions fitted snugly against the interior of the passage, and a cylindrical cavity coaxial with the rear radial aperture of the section, a pin is disposed within the cavity in the cap, a compression spring biases the pin radially outwardly so that an end portion thereof extends into the rear radial aperture of the section. 
     
     
       9. An extensible tool for handling energized electrical equipment comprising: a. a plurality of telescoping cylindrical tubular sections of insulating material each having a longitudinal passage and arranged in series so that the tool when extended is of reduced transverse cross section progressively from a rear to a forward end, each of the sections except a most rearward section having an outer diameter of such size that it slidably fits in the next rearwardly adjacent larger section;   b. a rearwardly facing annular interior shoulder positioned near the forward end of each of the sections except a most forward section;   c. a forwardly facing annular exterior shoulder positioned near the rearward end of each of the sections except the most rearward section;   d. a first radial aperture in each section except the most forward section positioned forwardly of and adjacent to the rearwardly facing shoulder of its section;   e. a second radial aperture in each section except the most rearward section positioned forwardly of and adjacent to the forwardly facing shoulder of its section;   f. each forwardly facing shoulder, when the tool is fully extended, being in engagement with the rearward facing shoulder of the next adjacent larger section and the first apertures being in substantial alignment respectively with the second apertures;   g. a pin support disposed within each section except the most rearward section and having a cavity coaxial with the second aperture of its section;   h. a pin and a spring disposed within each cavity, each spring biasing its associated pin radially outwardly for causing an end portion of its associated pin to extend into the second aperture of its section, and, when the tool is fully extended, for causing the end portion of its associated pin to extend into the first aperture of the next larger section, thereby to lock the sections in their extended positions with respect to each other; and   i. a rear radial aperture near the rearward end of the most rearward section having a cap positioned in the rearward end of the passage of the section, the cap having an apertured flange portion blocking entry to the passage, a shank portion provided with curved portions fitted snugly against the interior of the passage, and a cylindrical cavity coaxial with the rear radial aperture of the section, a pin disposed within the cavity in the cap and a compression spring for biasing the pin radially outwardly so that an end portion thereof extends into the rear radial aperture of the section.   
     
     
       10. An extensible tool as claimed in claim 9 wherein each annular exterior shoulder is defined by an edge face of a ring surrounding its associated section and bonded to the exterior surface of the section. 
     
     
       11. An extensible tool as claimed in claim 9 wherein each pin support only partially blocks the passage through its associated section and has opposed curved end portions fitted snugly against the interior of the passage. 
     
     
       12. An extensible tool as claimed in claim 9 wherein each first aperture is larger than its associated second aperture, each associated first and second aperture are positioned relative of each other when the shoulders of their respectve sections abut so that a gap exists between the forward side of the pin and the forward edge of the first aperture end whereby longitudinal pulling forces on the tool are borne only by the shoulders. 
     
     
       13. An extensible tool as claimed in claim 9 wherein each pin support has a rearward end face generally coplanar with the rearward end face of its associated section. 
     
     
       14. An extensible tool as claimed in claim 9 wherein each support has a diameter less than any portion of the rearward end of its associated section. 
     
     
       15. An extensible tool as claimed in claim 9 wherein the shoulders are radially disposed with respect to the longitudinal axes of their associated sections.